Extractors or baskets have been used for the removal of stones and other foreign objects from the urinary or biliary system. Often, the distal portion of these devices consist of a series of wires or strips that can be manipulated by the handle and actuating wire to expand to form an open basket. By further manipulating the handle of the extractor, the target object is captured within the basket, and the device is withdrawn from the body.
The procedure for extraction of a kidney stone usually requires that an endoscope be introduced to locate the obstruction. Once the stone is visualized, the basket or extractor is introduced through an operating lumen in the scope to complete the procedure. Occasionally, the extractor with the stone are too large to be safely withdrawn and further instrumentation such as forceps or an ultrasonic wire must be introduced that aid in fragmenting the object for removal. Without an additional operating lumen through which these instruments may be introduced, the endoscope must be withdrawn over the extractor. To accomplish this, the handle of the extractor must first be removed.
Handles for current extractors are end loaded with a hub or expanded portion at the proximal end of the actuating wires. The hubs locks into place with the handle mechanism. Unfortunately, however, they must be cut off the proximal end of the wire before the endoscope can be slid off the end of the extractor. This prevents reattachment and reuse of the handle to complete the procedure once the basket has been freed.
While handles have been developed that can be reused for subsequent medical procedures, none are known that can be used for situations as described above in which an endoscope can be readily removed and reintroduced during the same procedure without destruction of the actuating system. The ideal handle for a stone extractor must be able to be removed on a temporary basis and be easily reattached without the loss of handle function.